EP3652181A1 - An isohexide-dioxalate compound, its polymers and application thereof - Google Patents

An isohexide-dioxalate compound, its polymers and application thereof

Info

Publication number
EP3652181A1
EP3652181A1 EP18752874.0A EP18752874A EP3652181A1 EP 3652181 A1 EP3652181 A1 EP 3652181A1 EP 18752874 A EP18752874 A EP 18752874A EP 3652181 A1 EP3652181 A1 EP 3652181A1
Authority
EP
European Patent Office
Prior art keywords
dioxalate
formula
compound
furan
hexahydrofuro
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
EP18752874.0A
Other languages
German (de)
French (fr)
Inventor
Samir Hujur CHIKKALI
Kadhiravan Shanmuganathan
Bhausaheb RAJPUT
Farsa RAM
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Council of Scientific and Industrial Research CSIR
Original Assignee
Council of Scientific and Industrial Research CSIR
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Council of Scientific and Industrial Research CSIR filed Critical Council of Scientific and Industrial Research CSIR
Publication of EP3652181A1 publication Critical patent/EP3652181A1/en
Pending legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D493/00—Heterocyclic compounds containing oxygen atoms as the only ring hetero atoms in the condensed system
    • C07D493/02—Heterocyclic compounds containing oxygen atoms as the only ring hetero atoms in the condensed system in which the condensed system contains two hetero rings
    • C07D493/04—Ortho-condensed systems
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
    • C08G63/66—Polyesters containing oxygen in the form of ether groups
    • C08G63/668—Polyesters containing oxygen in the form of ether groups derived from polycarboxylic acids and polyhydroxy compounds
    • C08G63/672—Dicarboxylic acids and dihydroxy compounds

Definitions

  • the present invention relates to an isohexide-dioxalate compound of formula (I). More particularly, the present invention relates to an isohexide-dioxalates compound of formula (I), a process for preparation and use thereof. The present invention further relates to a polyoxalates compound of formula (II), a process for preparation and use thereof.
  • sugars can be easily converted to a host of new building blocks and it has naturally inbuilt chirality so it can be creatively utilized to manufacturing of value added chiral reagents.
  • This sugar can be readily converted to bifunctional molecules called isohexides.
  • the beauty of this isohexides is that they are chiral, non-toxic and rigid. Due to this rigid of backbone, incorporation of isohexides in the polymer main-chain will increase the glass transition temperature of resulting polymers.
  • isohexides (1,4:3, 6-Dianhydrohexitols) refers to sugar derived diols, which consist of three major isomers namely, l,4:3,6-Dianhydro-D-glucitol (isosorbide,la), 1,4:3, 6-Dianhydro-D-mannitol (isomannide,lb) and 1,4:3,6- Dianhydro-L-iditol (isoidide, lc).
  • the common C6-sugars such as glucose and mannose that are derived from the maize, wheat and potatoes or cereal-based polysaccharides, can be hydrogenated to produce sorbitol and mannitol respectively. Further, double dehydration of sorbitol and mannitol end up with corresponding isosorbide and isomannide.
  • isohexides differ physical and chemical properties of the isomers, such as melting temperatures and reactivity of the hydroxyl groups.
  • the endo hydroxyl groups form intramolecular hydrogen bonds to the oxygen atoms of the opposite furan ring, whereas the exo hydroxyl groups are not involved in intramolecular hydrogen bonding.
  • isomannide with two en ohydroxyl groups is the least reactive compound compared with isoidide which has two ejcohydroxyl groups and should be more attractive for biochemical applications.
  • Isoidide shows a significantly higher reactivity, but unfortunately its precursor, L-idose, cannot be obtained from plant biomass asit is rare in nature.
  • the current approach to obtain isoidide goes via inversion of chiral centres of isomannide.
  • Easily accessible isomer such as isosorbide has attracted significant attention, because of orientation of the two hydroxyl group at C2 is exo and that at C5 is endo, due to which isosorbide is more reactive isomer compared to isomannide.
  • Direct utilization of these isohexides in polymerization end up with dark tar like polymer, which could be due to the limited reactivity of secondary -OH group and hydrogen bonding between -OH groups and ether ring oxygen.
  • the present invention provides the synthesis of novel class of renewable isohexide-dioxalates and their polymerization with diols to afford polyoxalates.
  • the main objective of the present invention is to provide an isohexide-dioxalates compound of formula (I) and a process for preparation thereof.
  • Another objective of the present invention is to provide a polyoxalates compound of formula (II) and a process for preparation thereof.
  • the present invention provides an isohexide-dioxalates compound of formula (I);
  • R is selected from the group consisting of Ci to C5 alkyl and Ci to C5 aliphatic chain with heteroatoms.
  • the isohexide-dioxalates compound of formula (I) is selected from the group consisting of (0,0'-((3R, 6R)-hexahydrofuro[3,2- ]furan-3,6- diyl) dimethyl dioxalate [isomannide-dioxalate],(0,0'-((3R, 6S)-hexahydrofuro[3,2- ]furan-3,6-diyl) dimethyl dioxalate[isosorbide-dioxalate] and (0,0'-((3S, 6S)- hexahydrofuro[3,2- ]furan-3,6-diyl) dimethyl dioxalate [isoidide-dioxalate] .
  • the isohexide-dioxalate compound of formula (I) is used as a crystallizing agent and as a monomer for synthesis of polyoxalates.
  • the present invention provides a process for the preparation of the isohexide-dioxalates compound of formula (I) comprising the steps of: a) adding n-BuLi to a solution of an isohexide in a solvent at temperature in the range of -78 °C to 40 °C to obtain a first reaction mixture and stirring the first reaction mixture at a temperature in the range of 25 °C to 30 °C for the period in the range of 1 to 2 hours to obtain a reaction solution; b) adding an alkyl chlorooxoacetate to the reaction solution of step (a) at temperature in the range of 0 °C to 5°C to obtain a second reaction mixture and stirring the second reaction mixture at temperature in the range of 25 °C to 30°C for the period in the range of 44 to 50 hours to obtain isohexide-dioxalates compound of formula (I).
  • the present invention provides a polyoxalates compound of formula (II);
  • n is selected from 1 to 23;
  • x is selected from 1-1000;
  • y is selected from 1-2000;
  • z is selected from 10 to 1000;
  • R is selected from the group consisting of Ci to Cs alkyl and Ci to Cs aliphatic chain with heteroatoms.
  • the present invention provides a process for the preparation of polyoxalates compound of formula (II) comprising adding a catalyst to a mixture of an isohexide-dioxalates of formula (I), a diol to obtain a reaction mixture and heating the reaction mixture at temperature in the range of 120 °C or 150 °C for the period in the range 1 to 3 hrs and stirring the heated reaction mixture at a temperature of 150 °C for a period in the range of 6 to 96 hours to obtain polyoxalates compound of formula (II).
  • Figure 1 Solution casting of P2(2a-3b) to obtain a transparent film with CSIR-NCL logo in the background.
  • Figure 4 GPC chromatogram of PI (2a-3a) in chloroform at room temperature 30 °C.
  • Figure 5 GPC chromatogram of P2 (2a-3b) in chloroform at room temperature 30 °C.
  • Figure 6 GPC chromatogram of P3 (2a-3c) in chloroform at room temperature 30 °C.
  • Figure 7 GPC chromatogram of P4 (2b-3a) in chloroform at room temperature 30 °C.
  • Figure 8 GPC chromatogram of P5 (2b-3b) in chloroform at room temperature 30 °C.
  • Figure 9 GPC chromatogram of P6 (2b-3c) in chloroform at room temperature 30 °C.
  • Figure 10 GPC chromatogram of P7 (2c-3a) in chloroform at room temperature 30 °C.
  • Figure 11 GPC chromatogram of P8 (2c-3b) in chloroform at room temperature 30°C.
  • Figure 12 GPC chromatogram of P9 (2c-3c) in chloroform at room temperature 30°C.
  • the present invention provides an isohexide-dioxalates compound of formula (I), a process for preparation and use thereof.
  • the present invention further relates to a polyoxalates compound of formula (II), a process for preparation and use thereof.
  • the present invention provides an isohexide-dioxalates compound of formula (I);
  • R is selected from the group consisting of Ci to Cs alkyl and Ci to Cs aliphatic chain with heteroatoms.
  • the isohexide-dioxalates compound of formula (I) is selected from the group consisting of (0,0'-((3R, 6R)-hexahydrofuro[3,2- ]furan-3,6-diyl) dimethyl dioxalate [isomannide-dioxalate], (0,0'-((3R, 6S)-hexahydrofuro[3,2- ]furan-3,6-diyl) dimethyl dioxalate[isosorbide-dioxalate] and (0,0'-((3S, 6S)-hexahydrofuro[3,2- ]furan-3,6- diyl) dimethyl dioxalate [isoidide-dioxalate] .
  • the isohexide-dioxalate compound of formula (I) is used as a crystallizing agent and as a monomer for the synthesis of polyoxalates.
  • the present invention provides a process for the preparation of the isohexide-dioxalates compound of formula (I) comprising the steps of: a) adding n-BuLi to a solution of an isohexide in a solvent at temperature in the range of -78 °C to 40 °C to obtain a first reaction mixture and stirring the first reaction mixture at a temperature in the range of 25 °C to 30 °C for the period in the range of 1 to 2 hours to obtain a reaction solution; b) adding an alkyl chlorooxoacetate to the reaction solution of step (a) at temperature in the range of 0 °C to 5 °C to obtain a second reaction mixture and stirring the second reaction mixture at temperature in the range of 25 °C to 30 °C for the period in the range of 44-50 hours to obtain isohexide-dioxalates compound of formula (I).
  • the isohexide is selected from the group consisting of isomannide, isosorbide and isoidide.
  • the solvent is selected from the group consisting of tetrahydrofuran (THF), diethyl ether, toluene, dimethoxy ether, and dioxane or combination thereof.
  • the alkyl chlorooxoacetate is selected from the group consisting of methyl chlorooxoacetate, ethyl chlorooxoacetate, oxalic acid monoethyl ester and ethyl glyoxalate.
  • the present invention provides a polyoxalates compound of formula (II);
  • n is selected from 1 to 23;
  • x is selected from 1-1000;
  • y is selected from 1-2000;
  • z is selected from 10 to 1000;
  • R is selected from the group consisting of Ci to Cs alkyl and Ci to Cs aliphatic chain with heteroatoms.
  • the polyoxalates compound of formula (II) is represented by
  • the present invention provides a process for the preparation of polyoxalates compound of formula (II) comprising adding a catalyst to a mixture of an isohexide-dioxalates of formula (I), a diol to obtain a reaction mixture and heating the reaction mixture at temperature in the range of 120 °C or 150 °C for the period in the range 1 to 3 hrs and stirring the heated reaction mixture at a temperature of 150 °C for a period in the range of 6 to 96 hours to obtain polyoxalates compound of formula (II).
  • the catalyst is selected from the group consisting of /?-Toluenesulfonic acid, methane sulfonic acid, trifuloromethane sulfonic acid, titanium methoxide, titanium ethoxide, titanium isopropoxide and titanium tert-butaoxide.
  • the isohexide-dioxalates compound of formula (I) is selected from the group consisting of (0,0'-((3R, 6R)-hexahydrofuro[3,2- ]furan-3,6-diyl) dimethyl dioxalate [isomannide-dioxalate], (0,0'-((3R, 6S)-hexahydrofuro[3,2- ]furan-3,6-diyl) dimethyl dioxalate[isosorbide-dioxalate] and (0,0'-((3S, 6S)-hexahydrofuro[3,2- ]furan-3,6- diyl) dimethyl dioxalate [isoidide-dioxalate] .
  • the diol is selected from the group consisting of hexane-l,6-diol (3a), octane- 1,8-diol (3b), dodecane-l,12-diol (3c), decane-l,10-diol, nonadecane-1, 19-diol and tricosane- 1,23-diol.
  • the reaction is carried out under argon atmosphere.
  • the polyoxalates compound of formula (II) is used for the preparation of films and fibers, composites and fibers.
  • the polyoxalates of formula (II) are characterized using a combination of spectroscopic and analytical methods.
  • the formation of high molecular weight polyoxalate PI (2a- 3a)-P9(2c-3c) is confirmed by the reduced intensity of a proton resonance at around 3.89-3.91 although these signals overlap with backbone signals and absence of a 13 C peak at 53 ppm (corresponding to terminal -OCH 3 group).
  • the ratio of eight backbone protons of 2b (1:3: 1: 1:2) is retained in P5(2b-3b).
  • the splitting pattern of the polymer backbone protons is similar to that of 2b protons; suggesting that the stereochemistry of the monomer 2b is most likely preserved during the polymerization.
  • bMol. wt. and polydispersity index (PDI) were obtained from GPC in
  • the highest molecular weight polyoxalates P2(2a-3b) (Run-2, table 1) are tested for making film by solution casting.
  • Mechanical properties of as prepared film are measured on Dynamic Mechanical Analyzer (DMA).
  • DMA Dynamic Mechanical Analyzer
  • strength and elongation increases with increased molecular weight. This is due to increased entanglements of chains with increased molecular weight. In case of long entangled chains, it requires higher stress to get fully extended.
  • Low molecular weight polymer contains less entangled short chains which easily can be slipped upon applying stress.
  • the formation of films (Fig. 1) prove that synthesized polymer has enough molecular weight with chain entanglements to form a network structure.
  • the present invention also provides a synthesis of renewable feedstock chemicals with a degradable oxalate group incorporated into the building block.
  • the synthetic utility of these feedstock chemicals is demonstrated by preparing corresponding film forming, high molecular weight, degradable, polyoxalates via an intriguing dioxalate-diol cross metathesis polymerization reaction.
  • Example 4 Polymerization of isohexide-dioxalate (2a-c) and diols (3a-c) to polyoxalates PI (2a-3a)-P9(2c-3c):
  • the polyoxalates were prepared in a 50 ml Schlenk tube equipped with an overhead mechanical stirrer, heating arrangement and vacuum-purge system. Isohexide- dioxalates (2a-c) and linear-diols (3a-c) were transferred to the schlenk tube and the catalyst (1 mol%) of titanium isopropoxide was added under positive argon flow. The monomers (neat monomers) were melted by heating and polymerization was started at 120°C. Next, over a period of 2 hours the temperature was raised to 150 °C with intermittent vacuum after every 3-5 minutes to knock-off the byproduct (methanol). Finally, the polymer melt was stirred for next 46 hours under reduced pressure (0.01 mbar).
  • Example 6 Film preparation of poly oxalate P2(2a-3b) by solution casting:
  • a 10wt% polymer solution was prepared in chloroform (3 ml). Homogeneous polymer solution was poured in Teflon petri dish and was air dried in fume hood for 72 hours. The resultant film was sticky in nature and therefore it was further dried in a vacuum oven at 50°C for another 48h to remove any residual solvent present. Film was peeled off gently from Teflon petri dish and used as it is for mechanical characterization.
  • Novel isohexide-dioxalates are chiral compounds and can be used in many organic transformations.
  • the resultant polyoxalates can be drawn into transparent films.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Heterocyclic Carbon Compounds Containing A Hetero Ring Having Oxygen Or Sulfur (AREA)
  • Polyesters Or Polycarbonates (AREA)

Abstract

The present invention discloses an isohexide-dioxalates compound of formula (I), a process for preparation and use thereof. The present invention further discloses a polyoxalates compound of formula (II), a process for preparation and use thereof.

Description

AN ISOHEXIDE-DIOXALATE COMPOUND, ITS POLYMERS AND
APPLICATION THEREOF
FIELD OF THE INVENTION The present invention relates to an isohexide-dioxalate compound of formula (I). More particularly, the present invention relates to an isohexide-dioxalates compound of formula (I), a process for preparation and use thereof. The present invention further relates to a polyoxalates compound of formula (II), a process for preparation and use thereof.
BACKGROUND AND PRIOR ART OF THE INVENTION
Current situation of polymer industries is strongly dependent on monomers derived from non-renewable fossil feed-stock's. Due to depleting fossil feed-stock's and consequent increasing crude oil prices the scientific community is forced to find better alternatives. Therefore, use of renewable feed-stock could be the one of the better alternatives. Among the various renewable feedstock materials sugars, and plant oils can provide direct entry to chemical modification and functionalization. Along these lines, the renewable resource based products such as poly-lactic acid (PLA), polyhydroxyalkanoates (PHA) and sugar cane based polyethylene have been recently commercialized. It is appeared that the use of abundant renewable resources such as starch, cellulose and plant oilto develop new chemicals and polymeric materials seems to be a sustainable solution. For instance, sugars can be easily converted to a host of new building blocks and it has naturally inbuilt chirality so it can be creatively utilized to manufacturing of value added chiral reagents. This sugar can be readily converted to bifunctional molecules called isohexides. The beauty of this isohexides is that they are chiral, non-toxic and rigid. Due to this rigid of backbone, incorporation of isohexides in the polymer main-chain will increase the glass transition temperature of resulting polymers. The term isohexides (1,4:3, 6-Dianhydrohexitols) refers to sugar derived diols, which consist of three major isomers namely, l,4:3,6-Dianhydro-D-glucitol (isosorbide,la), 1,4:3, 6-Dianhydro-D-mannitol (isomannide,lb) and 1,4:3,6- Dianhydro-L-iditol (isoidide, lc). The common C6-sugars such as glucose and mannose that are derived from the maize, wheat and potatoes or cereal-based polysaccharides, can be hydrogenated to produce sorbitol and mannitol respectively. Further, double dehydration of sorbitol and mannitol end up with corresponding isosorbide and isomannide.
Among these isohexides the difference is only configuration of the two hydroxyl group located at C2 and C5 position to the bicyclic ether ring. In case of isomannide the configuration of -OH group at C2 and C5 position is endo-endo, whereas in case of isosorbide is endo-exo and in isoidide is exo-exo. Due to this difference in orientation of free hydroxyl groups, isohexides differ physical and chemical properties of the isomers, such as melting temperatures and reactivity of the hydroxyl groups. The endo hydroxyl groups form intramolecular hydrogen bonds to the oxygen atoms of the opposite furan ring, whereas the exo hydroxyl groups are not involved in intramolecular hydrogen bonding. Considering the steric effects and hydrogen bonding, isomannide with two en ohydroxyl groups is the least reactive compound compared with isoidide which has two ejcohydroxyl groups and should be more attractive for biochemical applications. Isoidide shows a significantly higher reactivity, but unfortunately its precursor, L-idose, cannot be obtained from plant biomass asit is rare in nature. The current approach to obtain isoidide goes via inversion of chiral centres of isomannide. Easily accessible isomer such as isosorbide has attracted significant attention, because of orientation of the two hydroxyl group at C2 is exo and that at C5 is endo, due to which isosorbide is more reactive isomer compared to isomannide. Direct utilization of these isohexides in polymerization end up with dark tar like polymer, which could be due to the limited reactivity of secondary -OH group and hydrogen bonding between -OH groups and ether ring oxygen.
Article titled "Polyoxalates from biorenewable diols via Oxalate Metathesis Polymerization" by John J. Garcia et al. published in Polymer Chemistry, 2014, 5, 955- 961 reports a method to prepare polyoxalates via an intermediate which was proposed to be a mono-oxalate. However, neither mono-oxalate nor di-oxalate was isolated. Furthermore, existence of such mono-oxalate or di-oxalate species was not proved. The prior art does not mention any application such as film, fibers and composites etc. The prior art uses partly renewable and partly fossil fuel derived monomers such as aromatic monomers.
The direct utilization of isohexides in polymerization leads to dark tar like materials. Apart from renewable origin, degradability is another material requirement for sustainable future.
Therefore, there is need to develop a synthetic strategy that can provide direct access to dioxalates monomers derived from renewable resources such as sugars and plant oils. Such monomers, if made accessible, can be used to obtain renewable polymers. If the resultant polymers are degradable, the approach will be a fully sustainable approach from cradle to grave. Thus, to satisfy the sustainability criteria, an approach that makes use of renewable resources, yields materials that can meet societal demand and degrades in environment without any adverse effect, will be highly desirable. Accordingly, the present invention provides the synthesis of novel class of renewable isohexide-dioxalates and their polymerization with diols to afford polyoxalates.
OBJECTIVES OF THE INVENTION
The main objective of the present invention is to provide an isohexide-dioxalates compound of formula (I) and a process for preparation thereof. Another objective of the present invention is to provide a polyoxalates compound of formula (II) and a process for preparation thereof.
SUMMARY OF THE INVENTION
Accordingly, the present invention provides an isohexide-dioxalates compound of formula (I);
Formula (I) wherein
R is selected from the group consisting of Ci to C5 alkyl and Ci to C5 aliphatic chain with heteroatoms.
In a preferred embodiment, the isohexide-dioxalates compound of formula (I) is selected from the group consisting of (0,0'-((3R, 6R)-hexahydrofuro[3,2- ]furan-3,6- diyl) dimethyl dioxalate [isomannide-dioxalate],(0,0'-((3R, 6S)-hexahydrofuro[3,2- ]furan-3,6-diyl) dimethyl dioxalate[isosorbide-dioxalate] and (0,0'-((3S, 6S)- hexahydrofuro[3,2- ]furan-3,6-diyl) dimethyl dioxalate [isoidide-dioxalate] .
The isohexide-dioxalate compound of formula (I) is used as a crystallizing agent and as a monomer for synthesis of polyoxalates.
In yet another embodiment, the present invention provides a process for the preparation of the isohexide-dioxalates compound of formula (I) comprising the steps of: a) adding n-BuLi to a solution of an isohexide in a solvent at temperature in the range of -78 °C to 40 °C to obtain a first reaction mixture and stirring the first reaction mixture at a temperature in the range of 25 °C to 30 °C for the period in the range of 1 to 2 hours to obtain a reaction solution; b) adding an alkyl chlorooxoacetate to the reaction solution of step (a) at temperature in the range of 0 °C to 5°C to obtain a second reaction mixture and stirring the second reaction mixture at temperature in the range of 25 °C to 30°C for the period in the range of 44 to 50 hours to obtain isohexide-dioxalates compound of formula (I).
In still another embodiment, the present invention provides a polyoxalates compound of formula (II);
Formula (II) wherein
n is selected from 1 to 23;
x is selected from 1-1000;
y is selected from 1-2000;
z is selected from 10 to 1000;
R is selected from the group consisting of Ci to Cs alkyl and Ci to Cs aliphatic chain with heteroatoms.
In yet still another embodiment, the present invention provides a process for the preparation of polyoxalates compound of formula (II) comprising adding a catalyst to a mixture of an isohexide-dioxalates of formula (I), a diol to obtain a reaction mixture and heating the reaction mixture at temperature in the range of 120 °C or 150 °C for the period in the range 1 to 3 hrs and stirring the heated reaction mixture at a temperature of 150 °C for a period in the range of 6 to 96 hours to obtain polyoxalates compound of formula (II).
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1. Solution casting of P2(2a-3b) to obtain a transparent film with CSIR-NCL logo in the background.
Figure 2: Stress-strain curve of P2(2a-3b).
Figure 3. Storage and loss modulus of P2(2a-3b).
Figure 4: GPC chromatogram of PI (2a-3a) in chloroform at room temperature 30 °C. Figure 5: GPC chromatogram of P2 (2a-3b) in chloroform at room temperature 30 °C. Figure 6: GPC chromatogram of P3 (2a-3c) in chloroform at room temperature 30 °C. Figure 7: GPC chromatogram of P4 (2b-3a) in chloroform at room temperature 30 °C. Figure 8: GPC chromatogram of P5 (2b-3b) in chloroform at room temperature 30 °C. Figure 9: GPC chromatogram of P6 (2b-3c) in chloroform at room temperature 30 °C. Figure 10: GPC chromatogram of P7 (2c-3a) in chloroform at room temperature 30 °C. Figure 11: GPC chromatogram of P8 (2c-3b) in chloroform at room temperature 30°C. Figure 12: GPC chromatogram of P9 (2c-3c) in chloroform at room temperature 30°C.
DETAILED DESCRIPTION OF THE INVENTION
The invention will now be described in detail in connection with certain preferred and optional embodiments, so that various aspects thereof may be more fully understood and appreciated.
The present invention provides an isohexide-dioxalates compound of formula (I), a process for preparation and use thereof. The present invention further relates to a polyoxalates compound of formula (II), a process for preparation and use thereof.
In an embodiment, the present invention provides an isohexide-dioxalates compound of formula (I);
Formula (I) wherein
R is selected from the group consisting of Ci to Cs alkyl and Ci to Cs aliphatic chain with heteroatoms. The isohexide-dioxalates compound of formula (I) is selected from the group consisting of (0,0'-((3R, 6R)-hexahydrofuro[3,2- ]furan-3,6-diyl) dimethyl dioxalate [isomannide-dioxalate], (0,0'-((3R, 6S)-hexahydrofuro[3,2- ]furan-3,6-diyl) dimethyl dioxalate[isosorbide-dioxalate] and (0,0'-((3S, 6S)-hexahydrofuro[3,2- ]furan-3,6- diyl) dimethyl dioxalate [isoidide-dioxalate] .
The isohexide-dioxalate compound of formula (I) is used as a crystallizing agent and as a monomer for the synthesis of polyoxalates.
In yet another embodiment, the present invention provides a process for the preparation of the isohexide-dioxalates compound of formula (I) comprising the steps of: a) adding n-BuLi to a solution of an isohexide in a solvent at temperature in the range of -78 °C to 40 °C to obtain a first reaction mixture and stirring the first reaction mixture at a temperature in the range of 25 °C to 30 °C for the period in the range of 1 to 2 hours to obtain a reaction solution; b) adding an alkyl chlorooxoacetate to the reaction solution of step (a) at temperature in the range of 0 °C to 5 °C to obtain a second reaction mixture and stirring the second reaction mixture at temperature in the range of 25 °C to 30 °C for the period in the range of 44-50 hours to obtain isohexide-dioxalates compound of formula (I).
The isohexide is selected from the group consisting of isomannide, isosorbide and isoidide.
The solvent is selected from the group consisting of tetrahydrofuran (THF), diethyl ether, toluene, dimethoxy ether, and dioxane or combination thereof.
The alkyl chlorooxoacetate is selected from the group consisting of methyl chlorooxoacetate, ethyl chlorooxoacetate, oxalic acid monoethyl ester and ethyl glyoxalate.
The process for the preparation of the isohexide-dioxalates is as depicted in scheme 1:
i) n-BuLi, -78°C,1 h and 1 h at RT; ii) CH3OCOCOCI, RT, 48h.
Schemel: Preparation of isohexide-dioxalates.
The attempts to prepare polyoxalates using isohexides and dimethyl oxalates in the presence of an acid catalyst such as /?-toluenesulfonic acid end up in dark tar like material (Scheme 2). The limited reactivity of isohexide is due to the sterically encumbered secondary hydroxyl groups. To improve the reactivity, isohexides are functionalized with methyl chlorooxoacetate to make AA type monomers (i.e. isohexide-dioxalates) (Scheme 2). This isohexide-dioxalates is subjected to polymerization with diols in presence of titanium isopropoxide to give the corresponding polyoxalates (Scheme 2).
Scheme 2: Classical method (top) and our approach (bottom) for acylating terminal hydroxyl groups to dioxalate and subsequent polymerization with diols to corresponding polyoxalates.
In still another embodiment, the present invention provides a polyoxalates compound of formula (II);
Formula (II)
wherein n is selected from 1 to 23;
x is selected from 1-1000;
y is selected from 1-2000;
z is selected from 10 to 1000;
R is selected from the group consisting of Ci to Cs alkyl and Ci to Cs aliphatic chain with heteroatoms.
The polyoxalates compound of formula (II) is represented by
Poly(Hexyl (6-(2-oxo-2-(((3R,6R)-6-(2-oxoacetoxy)hexahydrofuro[3,2-b]furan-3- yl)oxy)acetoxy)hexyl)) oxalate [Pl(2a-3a)],
Poly(Octyl (8-(2-oxo-2-(((3R,6R)-6-(2-oxoacetoxy)hexahydrofuro[3,2-b]furan-3- yl)oxy)acetoxy)octyl)) oxalate [P2(2a-3b)],
Poly(Dodecyl (12-(2-oxo-2-(((3R,6R)-6-(2-oxoacetoxy)hexahydrofuro[3,2-b]furan-3- yl)oxy)acetoxy)dodecyl)) oxalate [P3(2a-3c)], Poly(Hexyl (6-(2-oxo-2-(((3S,6R)-6-(2-oxoacetoxy)hexahydrofuro[3,2-b]furan-3- yl)oxy)acetoxy)hexyl)) oxalate [P4(2b-3a)],
Poly(Octyl(8 -(2-oxo-2-(((3 S ,6R)-6-(2-oxoacetoxy )hexahydrofuro [3 ,2-b] furan-3 - yl)oxy)acetoxy)octyl)) oxalate [P5(2b-3b)],
Poly(Dodecyl ( 12-(2-oxo-2-(((3 S ,6R)-6-(2-oxoacetoxy)hexahydrofuro [3 ,2-b] furan-3 - yl)oxy)acetoxy)dodecyl)) oxalate [P6(2b-3c)],
Poly(Hexyl (6-(2-oxo-2-(((3 S ,6S )-6-(2-oxoacetoxy)hexahydrofuro [3 ,2-b] furan-3 - yl)oxy)acetoxy)hexyl)) oxalate [P7(2c-3a)],
Poly(Octyl (8-(2-oxo-2-(((3S,6S)-6-(2-oxoacetoxy)hexahydrofuro[3,2-b]furan-3- yl)oxy)acetoxy)octyl)) oxalate [P8(2c-3b)], and Poly(Dodecyl ( 12-(2-oxo-2-(((3 S ,6S )-6-(2-oxoacetoxy)hexahydrofuro [3 ,2-b] furan-3 - yl)oxy)acetoxy)dodecyl)) oxalate [P9(2c-3c)].
The molecular weight of the polyoxalates compound of formula (II) is in the range of 2000 to 220000g/mol. In yet still another embodiment, the present invention provides a process for the preparation of polyoxalates compound of formula (II) comprising adding a catalyst to a mixture of an isohexide-dioxalates of formula (I), a diol to obtain a reaction mixture and heating the reaction mixture at temperature in the range of 120 °C or 150 °C for the period in the range 1 to 3 hrs and stirring the heated reaction mixture at a temperature of 150 °C for a period in the range of 6 to 96 hours to obtain polyoxalates compound of formula (II).
The catalyst is selected from the group consisting of /?-Toluenesulfonic acid, methane sulfonic acid, trifuloromethane sulfonic acid, titanium methoxide, titanium ethoxide, titanium isopropoxide and titanium tert-butaoxide.
The isohexide-dioxalates compound of formula (I) is selected from the group consisting of (0,0'-((3R, 6R)-hexahydrofuro[3,2- ]furan-3,6-diyl) dimethyl dioxalate [isomannide-dioxalate], (0,0'-((3R, 6S)-hexahydrofuro[3,2- ]furan-3,6-diyl) dimethyl dioxalate[isosorbide-dioxalate] and (0,0'-((3S, 6S)-hexahydrofuro[3,2- ]furan-3,6- diyl) dimethyl dioxalate [isoidide-dioxalate] .
The diol is selected from the group consisting of hexane-l,6-diol (3a), octane- 1,8-diol (3b), dodecane-l,12-diol (3c), decane-l,10-diol, nonadecane-1, 19-diol and tricosane- 1,23-diol.
The reaction is carried out under argon atmosphere. The polyoxalates compound of formula (II) is used for the preparation of films and fibers, composites and fibers.
The process for the synthesis of polyoxalates from isohexide-dioxalates and diols is as depicted in scheme 3:
HOJ OH
12
3c = 1 ,12-diol
Ti(OiPr)4
Isohexide-polyoxalates
Scheme3: Synthesis of polyoxalates Pl(2a-3b)-P7(2c-3c)
The polyoxalates of formula (II) are characterized using a combination of spectroscopic and analytical methods. The formation of high molecular weight polyoxalate PI (2a- 3a)-P9(2c-3c) is confirmed by the reduced intensity of a proton resonance at around 3.89-3.91 although these signals overlap with backbone signals and absence of a 13C peak at 53 ppm (corresponding to terminal -OCH3group). The ratio of eight backbone protons of 2b (1:3: 1: 1:2) is retained in P5(2b-3b).The splitting pattern of the polymer backbone protons is similar to that of 2b protons; suggesting that the stereochemistry of the monomer 2b is most likely preserved during the polymerization. These typical features are associated with all other polyoxalates derived from isomannide and isoidide.
In a decisive long-range through bond C-H correlation experiment (HMBC), an oxalate carbon ("E" carbon) at around 157-158 ppm revealed through bond correlation to protons at 5.3 ("D" proton that originates from the isosorbide backbone) and 4.2 ppm ("F" protons from the long-chain aliphatic segment). The 4.2 ppm "F" protons further displayed cross peaks to methylene carbons (G and H) in the range of 25-29 ppm. Thus, the above NMR experiments unambiguously prove the existence of anticipated polyoxalate and demonstrate through bond correlation between "D-E-E-F" type protons and carbons. Polymerization conditions like time, temperature and catalyst loading are optimized to get the highest molecular weight polymer and which is monitored by GPC.
The gel permeation chromatography (GPC) investigation of the polyoxalates PI (2a- 3a)-P9(2c-3c) revealed a molecular weight in the range of 14000-68000 g/mol (Run 1- 9, table 1) which is achieved using 1 mol% of catalyst and polymerization time is 48 hours. Thermal properties of polyoxalate are determined by differential scanning colorimetry (DSC). Polyoxalates derived from long chain diols displayed higher melting temperature compared to their shorter chain analogue (Table 1).
Table 1: Polyoxalates derived from the renewable feedstocks and their properties a
* Conditions: 2a-b: 3.14 mmol, 3a-c: 3.14 raraol, Ti(OiPr)4: 0.0314 tntnol
(1 mol%), Temp.: 120-150 °C, Time: 48 h, Yields are listed in
Table 2.
bMol. wt. and polydispersity index (PDI) were obtained from GPC in
chloroform with respect to polystyrene standards.
Obtained from DSC measurements.
d2a/2c and 3b=2.61 mmol.
e2a and 3c=2.47 mmol.
*2b and 3b=2.02 mmol.
g2b and 3c=2.68 mmol.
K2c and 3a/3c=2.83 mmol. NO=could not be observed.
The highest molecular weight polyoxalates P2(2a-3b) (Run-2, table 1) are tested for making film by solution casting. Mechanical properties of as prepared film are measured on Dynamic Mechanical Analyzer (DMA). There is minimum molecular weight requirement to form an entanglement networked structure of chains. It is also known that strength and elongation increases with increased molecular weight. This is due to increased entanglements of chains with increased molecular weight. In case of long entangled chains, it requires higher stress to get fully extended. Low molecular weight polymer contains less entangled short chains which easily can be slipped upon applying stress. The formation of films (Fig. 1) prove that synthesized polymer has enough molecular weight with chain entanglements to form a network structure.
Due to increased molecular weight there is more number of chains possibilities to form a highly intertwined chain network. The intertwined network of long chains makes it more resistant to respond for a mechanical stress. Stress and strain at break behavior as shown in (Fig 2) and table 2 summarizes the most significant data. Table 2: Strain and stress at break of P2(2a-3b).
After having established the reactivity, polymerization conditions are optimized and Table 1 summarizes the most significant results. The present invention also provides a synthesis of renewable feedstock chemicals with a degradable oxalate group incorporated into the building block. The synthetic utility of these feedstock chemicals is demonstrated by preparing corresponding film forming, high molecular weight, degradable, polyoxalates via an intriguing dioxalate-diol cross metathesis polymerization reaction.
Following examples are given by way of illustration therefore should not be construed to limit the scope of the invention.
EXAMPLES
Example 1: Synthesis of isomannide-dioxalate (2a):
To a stirred solution of isomannide (0.516 g, 3.53 mmol in 20 ml dry THF) was slowly added the n-BuLi(4.1 ml, 8.12 mmol) at -78 °C and the mixture stirred for 1 hour. After that, the resulting mixture is stirred at room temperature (30 °C) for over a period of 1 hour. To this mixture was added methyl chlorooxoacetate (0.74 ml, 8.12 mmol) at 0 °C and it was further stirred for next 48 hours at room temperature (30 °C). The reaction mixture was washed with saturated sodium chloride solution (20ml) and the aqueous phase was extracted with ethyl acetate (3 x 20 ml). The combined organic phase was dried over MgS04, filtered and the filtrate was evaporated in vacuum to obtain a highly viscous material. Purification by column chromatography (pet ether-ethyl acetate 55:45) resulted in highly viscous liquid. To this residue ethyl acetate was added and white solid was formed after addition of excess pet ether to ethylene acetate solution. The white solid was isolated after evaporation of solvents yielding 0.94 g of the desired isomannide-dioxalate (84%) as a white solid.
¾ NMR (400 MHz, CDC13, 298 Κ)δ = 5.20-5.16 (m, 2HD), 4.80-4.79 (m, 2HC), 4.08- 3.97 (m, 4HB), 3.89 (s, 6HA); 13C NMR (100 MHz, CDCI3, 298 K) δ = 157. 6-156.9 (s, CE), 80.1 (s, Cc), 75.7 (s, CD), 70.3 (s, CB), 53.8 (s, CA). ESI-MS (+ve mode) m/z = 341.04 [M+Na]+; Elemental analysis (%) calculated for Ci2Hi4Oio: C- 45.29%, H- 4.43%; Found : C- 45.97%, H-4.23%.
Example 2: Synthesis of isosorbide-dioxalate (2b):
To a stirred solution of isosorbide (0.516 g, 3.53mmol in 20 ml dry THF) was slowly added n-BuLi(4.1 ml, 8.12mmol) at -78 °C and the mixture is stirred for 1 hour. After that resulting mixture is stirred at room temperature (30 °C) for additional 1 hour. To this mixture was added methyl chlorooxoacetate (0.74 ml, 8.12mmol) at 0 °C and the reaction was stirred for next 48 hours at room temperature (30 °C). Subsequently, the reaction mixture was washed with saturated sodium chloride solution (20ml) and the aqueous phase was extracted with ethyl acetate (3 x 20 ml). The combined organic phase was dried over MgS04, filtered and the filtrate was evaporated in vacuum to obtain a highly viscous material. Purification by column chromatography (pet ether- ethyl acetate 55:45) obtained highly viscous liquid. This residue was dissolved in ethyl acetates and was precipitated as a white solid after addition of excess pet ether. The white solid was isolated after evaporation of solvents yielding 0.85 g of the desired isosorbide-dioxalate (2b) (76 %) as a white solid.
¾ NMR (400 MHz, CDC13, 298 Κ)δ = 5.33-5.30 (m, 2HD), 5.01-4.98 (m, 1HC), 4.59- 4.58 (m, lHc), 4.08-3.94 (m, 4HB), 3.91-3.89 (s, 6HA); 13C NMR (100 MHz, CDC1 , 298 K) δ = 157.7-156.8 (s, CE), 85.8 (s, Cc), 80.9 (s, Cc), 80.3 (s, CD), 76.2 (s, CD), 73.1 (s, CB), 70.8 (s, CB), 53.9 (s, CA). ESI-MS (+ve mode) m/z = 341.04 [M+Na]+; Elemental analysis (%) calculated for Ci2Hi4Oio: C- 45.29%, H- 4.43%; Found :C- 45.90%, H-4.33%.
Example 3: Synthesis of isoidide-dioxalate (2c):
To a stirred solution of isoidide (0.516 g, 3.53mmol in 20 ml dry THF) was slowly added the n-BuLi(4.1 ml, 8.12mmol) at -78 °C and the mixture was stirred for 1 hour. Next, the Schlenk tube was brought to room temperature (30 °C) and was stirred for an additional hour. Then, methyl chlorooxoacetate (0.74 ml, 8.12mmol) was added at 0 °C and further stirred for next 48 hours at room temperature (30 °C). The reaction mixture was washed with saturated sodium chloride solution (20ml) and the aqueous phase was extracted with ethyl acetate (3 x 20 ml). The combined organic phase was dried over MgS04, filtered and the filtrate was evaporated in vacuum to obtain a highly viscous material. Purification by column chromatography (pet ether-ethyl acetate 55:45) yielded a highly viscous liquid. This residue was dissolved in ethyl acetate and was precipitated by adding excess pet ether to produce white solid. The white solid was isolated after evaporation of solvents yielding 0.60 g of the desired isoidide-dioxalate (2c) (53%). ln NMR (400 MHz, CDCb, 298 Κ)δ = 5.33 (m, 2HD), 4.79 (m, 2HC), 4.02 (m, 4HB), 3.88 (s, 6HA); 13C NMR (100 MHz, CDCb, 298 K) δ = 157.2-156.3 (s, CE), 84.8 (s, Cc), 79.5 (s, CD), 71.9 (s, CB), 53.6 (s, CA). ESI-MS (+ve mode) m/z = 319.06 [M+H]+; Elemental analysis (%) calculated for Ci2Hi4Oio: C- 45.29%, H- 4.43%; Found : C- 45.15%, H-3.87%.
Example 4: Polymerization of isohexide-dioxalate (2a-c) and diols (3a-c) to polyoxalates PI (2a-3a)-P9(2c-3c):
The polyoxalates were prepared in a 50 ml Schlenk tube equipped with an overhead mechanical stirrer, heating arrangement and vacuum-purge system. Isohexide- dioxalates (2a-c) and linear-diols (3a-c) were transferred to the schlenk tube and the catalyst (1 mol%) of titanium isopropoxide was added under positive argon flow. The monomers (neat monomers) were melted by heating and polymerization was started at 120°C. Next, over a period of 2 hours the temperature was raised to 150 °C with intermittent vacuum after every 3-5 minutes to knock-off the byproduct (methanol). Finally, the polymer melt was stirred for next 46 hours under reduced pressure (0.01 mbar). The thus obtained polymer was dissolved in chloroform and precipitated by pouring in methanol (around 100 ml). The resultant polymers were isolated in semisolid material which was dried in vacuum. The quantitative details of various polyoxalates are summarized in table 3. Synthesized polyoxalates were characterized and representative NMR data were provided in following section.
Table 3: Polymerization of isohexide-dioxalates (2a-c) and linear-diols (3a-c)
P2(2a-3b) 0.83 (2.61) 0.38 (2.61) 0.0261 1.05 0.60 57
P3(2a-3c) 0.78 (2.47) 0.50 (2.47) 0.0247 1.13 0.77 68
P4(2b-3a) 1.0 (3.14) 0.37 (3.14) 0.0314 1.17 0.84 72
P5(2b-3b) 0.64 (2.02) 0.29 (2.02) 0.0202 0.81 0.50 62
P6(2b-3c) 0.85 (2.68) 0.54 (2.68) 0.0268 1.22 0.91 74
P7(2c-3a) 0.9 (2.83) 0.33 (2.83) 0.0283 1.05 0.69 65
P8(2c-3b) 0.83 (2.61) 0.38 (2.61) 0.0261 1.05 0.68 65
P9(2c-3c) 0.9 (2.83) 0.57 (2.83) 0.0283 1.29 0.95 74
Example 5: NMR data of poly oxalates: a) Pl(2a-3a):
¾ NMR (500 MHz, CDC13, 298K) 5 = 5.18 (br., 2HD), 4.80 (br., s, 2HC), 4.26 (br., s, 8HF), 4.07-3.98 (br., s, 4HB), 1.74 (br., s, 8HG), 1.42 (br., s, 8HH).13C NMR (125 MHz, CDCI3, 298K) δ = 157.9-156.4 (m, CE), 79.9 (s, Cc), 75.6 (s, CD), 70.2 (s, CB), 67.1- 66.8 (m, CF), 28.1 (s, Co), 25.3 (s, CH).
b) P2(2a-3b):
ln NMR (400 MHz, CDCb, 298K) 5 = 5.19 (br., 2HD), 4.81 (br., s, 2HC), 4.27 (br., s, 12HF), 4.06 (br., s, 4HB), 1.73 (br., s, 12HG), 1.36 (br., s, 23HH).13C NMR (100 MHz, CDCb, 298K) δ = 157.9-157.0 (m, CE), 79.8 (s, Cc), 75.4 (s, CD), 70.0 (s, CB), 66.9 (m, CF), 28.8 (s, Co), 28.1-25.4 (s, CH).
c) P3(2a-3c):
¾ NMR (400 MHz, CDCb, 298K) 5 = 5.18 (br., 2HD), 4.81 (br., s, 2HC), 4.26 (br., s, 8HF), 4.07-4.00 (br., s, 4HB), 1.72 (br., s, 9HG), 1.26 (br., s, 34HH).13C NMR (100 MHz, CDCb, 298K) δ = 157.9-157.1 (m, CE), 79.9 (s, Cc), 75.5 (s, CD), 70.1 (s, CB), 67.4-67.1 (m, CF), 29.4 (s, Co), 29.4, 29.1, 28.2, 25.6 (s, CH). d) P4(2b-3a):
¾ NMR (400 MHz, CDCb, 298K) δ = 5.31 (br., 2HD), 4.98 (br., s, 1HC), 4.58 (br., s, lHc), 4.26 (br., s, 6HF), 4.05 (br., s, 3HB), 3.92 (br., s, 1HB), 1.74 (br., s, 6HG), 1.42 (br., s, 6HH).13C NMR (100 MHz, CDCb, 298K) δ = 157.9-156.9 (m, CE), 85.7 (s, Cc), 80.8 (s, Cc), 80.1 (s, CD), 76.0 (s, CD), 72.9 (s, CB), 70.7 (s, CB), 67.1-66.8 (m, CF), 28.1 (s, CG), 25.3 (s, CH). e) P5(2b-3b):
ln NMR (500 MHz, CDCb, 298K) δ = 5.30 (br., 2HD), 4.97 (br., s, 1HC), 4.56 (br., s, lHc), 4.24 (br., s, 8HF), 4.04 (br., s, 3HB), 3.91-3.89 (br., s, 1HB), 1.70 (br., s, 8HG), 1.32 (br., s, 16HH).13C NMR (125 MHz, CDCb, 298K) δ = 158.0-157.0 (m, CE), 85.7 (s, Cc), 80.8 (s, Cc), 80.0 (s, CD), 75.9 (s, CD), 72.8 (s, CB), 70.7 (s, CB), 67.3-67.0 (m, CF), 28.9 (s, Co), 25.6 (s, CH).
f) P6(2b-3c):
lH NMR (400 MHz, CDCb, 298K) δ = 5.32 (br., 2HD), 4.99 (br., s, 1HC),4.59 (br., s, IHD), 4.27 (br., s, 6HF), 4.06 (br., s, 4HB), 1.72 (br., s, 7HG), 1.28 (br., s, 25HH).13C NMR (100 MHz, CDCb, 298K) δ = 158.0-157.0 (m, CE), 85.7 (s, Cc), 80.7 (s, Cc), 80.0 (s, CD), 76.2-75.9 (s, CD), 72.8 (s, CB), 70.7 (s, CB), 67.5-67.1 (m, CF), 29.4 (s, Co), 29.1-25.6 (s, CH).
g) P7(2c-3a): ln NMR (400 MHz, CDCb, 298K) δ = 5.31 (br., 2HD), 4.78 (br., s, 2HC), 4.26 (br., s, 8HF), 4.02 (br., s, 4HB), 1.73(br., s, 7HG), 1.42 (br., s, 7HH).13C NMR (100 MHz, CDCb, 298K) δ = 157.9-156.8 (m, CE), 85.0 (s, Cc), 80.0-79.7 (m, CD), 72.1 (s, CB), 67.1-66.8 (m, CF), 28.1 (s, Co), 25.3(s, CH).
h) P8(2c-3b):
¾ NMR (500 MHz, CDCb, 298K) δ= 5.32 (br., 2HD), 4.79 (br., s, 2Hc), 4.25 (br., s, 7HF), 4.02 (br., s, 4HB), 3.86 (br., 1HA), 1.71 (br., s, 7HG), 1.33 (br., s, 15HH).13C NMR (125 MHz, CDCb, 298K) δ = 158.0-156.8(m, CE), 85.1-85.0 (m, Cc), 79.7 (s, CD), 72.1-72.0 (m, CB), 67.4-67.0 (m, CF), 28.9 (s, Co), 28.2(s, CH), 25.6 (s, CH).
i) P9(2c-3c):
¾ NMR (500 MHz, CDCb, 298K) δ = 5.33 (br., 2HD), 4.80 (br., s, 2HC), 4.27 (br., s, 7HF), 4.04 (br., s, 4HB), 1.72 (br., s, 8HG), 1.28 (br., s, 27HH).13C NMR (125 MHz, CDCb, 298K) δ = 158.1-156.9 (m, CE), 85.2 (s, Cc), 80.1-79.7 (m, CD), 72.2 (s, CB), 67.6-67.2 (m, CF), 29.5 (s, Co), 29.2-25.7 (m, CH).
Example 6: Film preparation of poly oxalate P2(2a-3b) by solution casting:
A 10wt% polymer solution was prepared in chloroform (3 ml). Homogeneous polymer solution was poured in Teflon petri dish and was air dried in fume hood for 72 hours. The resultant film was sticky in nature and therefore it was further dried in a vacuum oven at 50°C for another 48h to remove any residual solvent present. Film was peeled off gently from Teflon petri dish and used as it is for mechanical characterization.
Advantages of the invention:
1) Use of sugar and plant oil derived molecules.
2) A single step synthetic protocol to prepare renewable isohexide-dioxalates.
3) Novel isohexide-dioxalates are chiral compounds and can be used in many organic transformations.
4) High molecular weight polyoxalates have been prepared.
5) The resultant polyoxalates can be drawn into transparent films.

Claims

We claim:
1 An isohexide-dioxalate compound of formula (I);
Formula (I) wherein
R is selected from the group consisting of Ci to C5 alkyl and Ci to C5 aliphatic chain with hetero atoms.
2. The compound of formula (I) as claimed in claim 1, wherein said compound is selected from the group consisting of (0,0'-((3R, 6R)-hexahydrofuro[3,2- b]furan-3,6-diyl) dimethyl dioxalate [isomannide-dioxalate],(0,0'-((3R, 6S)- hexahydrofuro[3,2-b]furan-3,6-diyl) dimethyl dioxalate[isosorbide-dioxalate] and (0,0'-((3S, 6S)-hexahydrofuro[3,2-b]furan-3,6-diyl) dimethyl dioxalate [isoidide-dioxalate] .
3. A process for the preparation of isohexide-dioxalate compound of formula (I) comprising the steps of: adding n-BuLi to a solution of an isohexide in a solvent at temperature in the range of -78 °C to 40 °C to obtain a first reaction mixture and stirring the first reaction mixture at a temperature in the range of 25 °C to 30 °C for the period in the range of 1 to 2 hours to obtain a reaction solution; adding an alkyl chlorooxoacetate to the reaction solution of step (a) at temperature in the range of 0 °C to 5 °C to obtain a second reaction mixture and stirring the second reaction mixture at temperature in the range of 25 °C to 30 °C for the period in the range of 44 to 50 hours to obtain isohexide-dioxalates compound of formula (I).
The process as claimed in claim 3, wherein said isohexide is selected from the group consisting of isomannide, isosorbide and isoidide; said solvent is selected from the group consisting of tetrahydrofuran, diethyl ether, toluene, dimethoxy ether, and dioxane or combination thereof; and said alkyl chlorooxoacetate is selected from the group consisting of methyl chlorooxoacetate, ethyl chlorooxoacetate, oxalic acid monoethyl ester and ethyl glyoxalate.
A polyoxalate compound of formula (II) is represented by
Formula (II) wherein n is selected from 1 to 23 ; x is selected from 1-1000; y is selected from 1-2000; z is selected from 10 to 1000;
R is selected from the group consisting of Ci to Cs alkyl and Ci to Cs aliphatic chain with hetero atoms. The polyoxalate compound of formula (II) as claimed in claim 5, wherein said compound is selected from group consisting of
Poly(Hexyl (6-(2-oxo-2-(((3R,6R)-6-(2-oxoacetoxy)hexahydrofuro[3,2-b]furan- 3-yl)oxy)acetoxy)hexyl)) oxalate [Pl(2a-3a)], Poly(Octyl (8-(2-oxo-2-(((3R,6R)-6-(2-oxoacetoxy)hexahydrofuro[3,2-b]furan- 3-yl)oxy)acetoxy)octyl)) oxalate [P2(2a-3b)],
Poly(Dodecyl (12-(2-oxo-2-(((3R,6R)-6-(2-oxoacetoxy)hexahydrofuro[3,2- b]furan-3-yl)oxy)acetoxy)dodecyl)) oxalate [P3(2a-3c)],
Poly(Hexyl (6-(2-oxo-2-(((3S,6R)-6-(2-oxoacetoxy)hexahydrofuro[3,2-b]furan- 3-yl)oxy)acetoxy)hexyl)) oxalate [P4(2b-3a)],
Poly(Octyl(8-(2-oxo-2-(((3S,6R)-6-(2-oxoacetoxy)hexahydrofuro[3,2-b]furan- 3-yl)oxy)acetoxy)octyl)) oxalate [P5(2b-3b)],
Poly(Dodecyl ( 12-(2-oxo-2-(((3 S ,6R)-6-(2-oxoacetoxy)hexahydrofuro [3 ,2- b]furan-3-yl)oxy)acetoxy)dodecyl)) oxalate [P6(2b-3c)],
Poly(Hexyl (6-(2-oxo-2-(((3S,6S)-6-(2-oxoacetoxy)hexahydrofuro[3,2-b]furan- 3-yl)oxy)acetoxy)hexyl)) oxalate [P7(2c-3a)],
Poly(Octyl (8-(2-oxo-2-(((3S,6S)-6-(2-oxoacetoxy)hexahydrofuro[3,2-b]furan- 3-yl)oxy)acetoxy)octyl)) oxalate [P8(2c-3b)], and
Poly(Dodecyl (12-(2-oxo-2-(((3S,6S)-6-(2-oxoacetoxy)hexahydrofuro[3,2- b]furan-3-yl)oxy)acetoxy)dodecyl)) oxalate [P9(2c-3c)].
7. The polyoxalate compound of formula (II) as claimed in claim 5, wherein molecular weight of said polyoxalate compound of formula (II) is in the range of 2000 to 220000g/mol.
8. A process for the preparation of compound of formula (II) as claimed in claim 5, wherein said process comprising i. adding a catalyst to a mixture of an isohexide-dioxalate of formula (I) as claimed in claim 1, and a diol to obtain a reaction mixture and heating the reaction mixture at temperature in the range of 120 °C or 150 °C for the period in the range 1 to 3 hrs; and ii. stirring the heated reaction mixture at a temperature of 150 °C for a period in the range of 6 to 96 hours to obtain polyoxalate compound of formula (II).
9. The process as claimed in claim 8, wherein said catalyst is selected from the group consisting of /?-toluenesulfonic acid, methane sulfonic acid, trifuloromethane sulfonic acid, titanium methoxide, titanium ethoxide, titanium isopropoxide and titanium tert-butoxide; and said diol is selected from the group consisting of hexane-l,6-diol (3a), octane- 1,8-diol (3b), dodecane-l,12-diol
(3c), decane-l,10-diol, nonadecane-1, 19-diol and tricosane-l,23-diol.
10. The process as claimed in claim 8, wherein said isohexide-dioxalates compound of formula (I) is selected from the group consisting of (0,0 '-((3R, 6R)- hexahydrofuro[3,2-b]furan-3,6-diyl) dimethyl dioxalate [isomannide-dioxalate], (0,0'-((3R, 6S)-hexahydrofuro[3,2-b]furan-3,6-diyl) dimethyl dioxalate[isosorbide-dioxalate] and (0,0'-((3S, 6S)-hexahydrofuro[3,2-b]furan- 3,6-diyl) dimethyl dioxalate [isoidide-dioxalate] .
EP18752874.0A 2017-07-12 2018-07-12 An isohexide-dioxalate compound, its polymers and application thereof Pending EP3652181A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IN201711024522 2017-07-12
PCT/IN2018/050457 WO2019012560A1 (en) 2017-07-12 2018-07-12 An isohexide-dioxalate compound, its polymers and application thereof

Publications (1)

Publication Number Publication Date
EP3652181A1 true EP3652181A1 (en) 2020-05-20

Family

ID=63165426

Family Applications (1)

Application Number Title Priority Date Filing Date
EP18752874.0A Pending EP3652181A1 (en) 2017-07-12 2018-07-12 An isohexide-dioxalate compound, its polymers and application thereof

Country Status (4)

Country Link
US (1) US12060363B2 (en)
EP (1) EP3652181A1 (en)
CN (1) CN111278832B (en)
WO (1) WO2019012560A1 (en)

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4208511A (en) * 1977-01-19 1980-06-17 Ethicon, Inc. Isomorphic copolyoxalates and sutures thereof
DE2938464A1 (en) * 1979-09-22 1981-04-09 Bayer Ag, 5090 Leverkusen THERMOPLASTIC POLYCARBONATES, THEIR PRODUCTION AND THEIR USE AS MOLDED BODIES AND FILMS
DE19704506A1 (en) * 1997-02-06 1998-08-13 Basf Ag Chiral nematic polyester
US6608167B1 (en) * 2002-03-26 2003-08-19 E. I. Du Pont De Nemours And Company Bis(2-hydroxyethyl isosorbide); preparation, polymers derived therefrom, and enduses thereby
US6818730B2 (en) * 2002-04-26 2004-11-16 E. I. Du Pont De Nemours And Company Process to produce polyesters which incorporate isosorbide
US6737481B1 (en) * 2002-12-19 2004-05-18 E. I. Du Pont De Nemours And Company Ester-modified dicarboxylate polymers
JP4692057B2 (en) * 2004-04-22 2011-06-01 宇部興産株式会社 New polyoxalate
WO2005103111A1 (en) 2004-04-22 2005-11-03 Ube Industries, Ltd. Poly(isosorbid oxalate) resin
JP2010503736A (en) * 2006-09-15 2010-02-04 スティッチング ダッチ ポリマー インスティテュート Process for the production of polyesters based on dianhydrohexitol
US9580544B2 (en) * 2010-03-18 2017-02-28 New Jersey Institute Of Technology Polyesters from asymetrical monomers based upon bisanhydrohexitols
JP6042909B2 (en) * 2012-01-17 2016-12-14 クローダ，インコーポレイティド Seal swelling additive
KR20160023973A (en) * 2014-08-21 2016-03-04 삼성정밀화학 주식회사 Transparent biodegradable polymers

Also Published As

Publication number Publication date
WO2019012560A1 (en) 2019-01-17
US20210147438A1 (en) 2021-05-20
WO2019012560A4 (en) 2019-03-07
CN111278832A (en) 2020-06-12
US12060363B2 (en) 2024-08-13
CN111278832B (en) 2024-04-12

Similar Documents

Publication Publication Date Title
Saxon et al. Next-generation polymers: Isosorbide as a renewable alternative
Fourcade et al. Renewable resource-based epoxy resins derived from multifunctional poly (4-hydroxybenzoates)
Huang et al. Exploration of the complementary properties of biobased epoxies derived from rosin diacid and dimer fatty acid for balanced performance
JP5468008B2 (en) Polyketal compounds, synthesis and applications
Hollande et al. ADMET polymerization of biobased monomers deriving from syringaresinol
KR20140105185A (en) Method for preparation of anhydrosugar alcohols with reduced formation of polymeric reaction byproducts
Tachibana et al. Synthesis and characterization of a renewable polyester containing oxabicyclic dicarboxylate derived from furfural
JP2018150415A (en) Furan oligomer polyester and precursor thereof
JP2017501147A (en) Synthesis of isohexide ether and isohexide carbonate.
US10759899B2 (en) Recyclable polymers based on ring-fused gamma-butyrolactones
Kieber et al. Cationic copolymerization of isosorbide towards value-added poly (vinyl ethers)
JP2016523240A (en) Synthesis of isohexide dicarbamate and its derivatives.
WO2016097657A2 (en) Polyaromatic dimers, method for preparing same and use of same
US12060363B2 (en) Isohexide-dioxalate compound, its polymers and application thereof
US8278449B2 (en) Thermally switchable ruthenium initiators
US9828387B2 (en) Control of color-body formation in isohexide esterification
KR101867506B1 (en) A 1,4:3,6-dianhydro-D-hexane-1,2,3,4,5,6-hexol derivative, a preparation method thereof and a polycarbonate prepared by using the same
JP2021161118A (en) Polymerizable alicyclic compound
US10047100B2 (en) Compounds from renewable resources
JP2017501138A (en) Improved glycol acylation process
US10377850B2 (en) Polyester stereocomplexes, compositions comprising same, and methods of making and using same
KR20140048439A (en) Method for preparation of anhydrosugar alcohols by using polyol as reaction diluent
US2134430A (en) Resinous reaction products of inner ethers and natural resin acids and methods of making the same
WO2014181358A2 (en) Isohexide-diacetal based polymers and a process thereof
KR20150139942A (en) Mono-ethers of isohexides and process for making the same

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: UNKNOWN

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20200109

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

AX Request for extension of the european patent

Extension state: BA ME

DAV Request for validation of the european patent (deleted)
DAX Request for extension of the european patent (deleted)
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: EXAMINATION IS IN PROGRESS

17Q First examination report despatched

Effective date: 20220510